Alkylation of benzene to form linear alkylbenzenes using fluorine-containing mordenites

ABSTRACT

This invention is directed to a fluorine-containing mordenite catalyst and use thereof in the manufacture of linear alkylbenzene (LAB) by alkylation of benzene with an olefin. The paraffin may have from about 10 to 14 carbons. The fluorine-containing mordenite is prepared typically by treatment with an aqueous hydrogen fluoride solution. The benzene alkylation may be conducted using reactive distillation. This invention is also directed to a process for production of LAB having a high 2-phenyl isomer content by combining LAB product from the fluorine-containing mordenite product from a conventional LAB alkylation catalyst such as hydrogen fluoride.

This application is a continuation-in-part application of applicationSer. No. 08/598,692, filed Feb. 8, 1996, now U.S. Pat. No. 5,847,254 andof application Ser. No. 08/879,745, filed Jun. 20, 1997, which is adivisional of Ser. No. 08/598,695, filed Feb. 8, 1996, now U.S. Pat. No.5,770,782, the contents of which are expressly incorporated herein byreference.

BACKGROUND OF THE INVENTION

This invention generally relates to the alkylation of benzene withparaffins using mordenite catalysts.

Linear alkylbenzenes (LAB's) having long chains (typically 10-14carbons) are commonly used, commercial products. LAB's are commonlysulfonated to thereby produce surfactants.

Typically, LAB's are manufactured commercially using classicFriedal-Crafts chemistry, employing catalysts such as aluminum chloride,or using strong acid catalysts such as hydrogen fluoride, for example,to alkylate benzene with paraffins. While such methods produce highconversions, the selectivity to the 2-phenyl isomer is low, generallybeing about 30% or less. LAB's with a high percentage of the 2-phenylisomer are highly desired because such compounds when sulfonated havelong "tails" which provide enhanced solubility and detergent properties.

SUMMARY OF THE INVENTION

It has now been recognized that a need exists for a method of LABproduction having high substrate olefin conversion, high selectivity to2-phenyl isomer LAB, and employing a catalyst having long lifetimes andeasy handling. This invention provides a solution to one or more of theproblems and disadvantages described above.

It has also been found that the catalyst of this invention may be usedin combination with an existing aluminum chloride or hydrogen fluoridealkylation facility to afford LAB having a higher 2-phenyl isomercontent than would otherwise be available from such plant. Thus, anexisting facility may be retrofitted to include one or more reactorscontaining the fluorine-containing mordenite of this invention. In thismanner, a slip stream of reactants may be sent to the mordenite witheffluent therefrom being introduced back into the conventionalalkylation system. This embodiment has several advantages. For example,the cost of capital is minimized since conventional equipment willalready be in place. Also, the retrofitted plant can produce higher2-phenyl isomer LAB at the discretion of its operator, depending onneed. That is, the plant need not produce strictly high 2-phenyl isomerLAB and can instead produce high 2-phenyl isomer at its discretion. Inone embodiment, a slip stream of reactant is drawn and sent to one ormore reactors containing fluorine-containing mordenite catalyst. Theeffluent from the fluorine-containing mordenite reactor may then becombined with effluent from the HF or aluminum chloride reactor toprovide a product having a higher level of 2-phenyl isomer LAB thanwould otherwise be present in product from an HF or aluminum chloridereactor.

This invention, in one broad respect, is a process useful for theproduction of monoalkylated benzene, comprising contacting benzene withan olefin containing from about 8 to about 30 carbons in the presence offluorine-containing mordenite under conditions such that linearmonoalkylated benzene is formed.

In another broad respect, this invention is a process for the productionof linear alkylbenzene, comprising:

contacting benzene and an olefin having about 8 to about 30 carbons inthe presence of a fluorine-containing mordenite to form a first linearalkylbenzene stream;

contacting benzene and an olefin having about 8 to about 30 carbons inthe presence of a conventional linear alkylbenzene alkylation catalystto form a second linear alkylbenzene stream;

combining the first linear alkylbenzene stream and the second linearalkylbenzene stream form a third linear alkylbenzene stream, as well asthe product made from this process.

In another broad respect, this invention is a process useful for theproduction of linear alkylbenzene, comprising:

combining a product from a conventional linear alkylbenzene alkylationreactor with a product from a linear alkylbenzene alkylation reactorcontaining fluorine-containing mordenite.

In yet another broad respect, this invention is a process for theproduction of linear alkylbenzene, comprising:

dehydrogenating a paraffin to form an olefin;

sending a primary feed stream of benzene and the olefin through aconduit to a conventional linear alkylbenzene alkylation reactor;

contacting the primary feed stream in the conventional linearalkylbenzene alkylation reactor with a conventional linear alkylbenzenealkylation catalyst under conditions effective to react the benzene andolefin to form a first linear alkylbenzene product;

withdrawing a portion of the primary feed stream from the conduit andcontacting the portion with a fluorine-containing mordenite underconditions effective to react the benzene and olefin to form a secondlinear alkylbenzene product;

combining the first and second linear alkylbenzene products to form acrude linear alkylbenzene stream;

distilling the crude linear alkylbenzene stream in a first distillationcolumn to separate benzene that did not react and to form a benzene-freelinear alkylbenzene stream;

optionally distilling the benzene-free linear alkylbenzene stream in asecond distillation column to separate any olefin and to form a linearalkylbenzene stream;

distilling the second olefin free alkylbenzene stream in a thirddistillation column to provide an overhead of a purified linearalkylbenzene product and removing a bottoms stream containing anyheavies.

In another broad respect, this invention is a process useful for theproduction of monoalkylated benzene, comprising introducing a feedcomprising olefin having about 8 to about 30 carbons and benzene into afluorine-containing mordenite catalyst bed under conditions such thatmonoalkylated benzene is produced, allowing benzene, olefin, andmonoalkylated benzene to descend (fall) into a reboiler from thecatalyst bed, removing monoalkylated benzene from the reboiler, andheating the contents of the reboiler such that benzene refluxes tofurther contact the fluorine-containing mordenite.

In another broad aspect, this invention relates to mordenite useful foralkylating benzene with olefin having a silica to alumina molar ratio ofabout 10:1 to about 100:1; wherein the mordenite has been treated withan aqueous hydrogen fluoride solution such that the mordenite containsfrom about 0.1 to about 4 percent fluorine by weight.

In another broad respect, this invention is a method useful for thepreparation of fluorine-containing mordenite, comprising contacting amordenite having a silica to alumina molar ratio in a range from about10:1 to about 100:1 with an aqueous hydrogen fluoride solution having aconcentration of hydrogen fluoride in the range of from about 0.1 toabout 10 percent by weight such that the mordenite containing fluorineis produced, collecting the fluorine-containing mordenite by filtration,and drying.

The fluorine treated mordenite catalyst advantageously produces highselectivities to the 2-phenyl isomer in the preparation of LAB,generally producing selectivities of about 70 percent or more. Also, thefluorine treated mordenite enjoys a long lifetime, preferablyexperiencing only a 25 percent or less decrease in activity after 400hours on stream. A process operated in accordance with the apparatusdepicted in FIGS. 1 and 2 has the advantage that rising benzene from thereboiler continuously cleans the catalyst to thereby increase lifetimeof the catalyst. In addition, this invention advantageously producesonly low amounts of dialkylated benzene, which is not particularly asuseful for detergent manufacture, as well as only low amounts oftetralin derivatives.

Certain terms and phrases have the following meanings as used herein.

"Meq/g" means milliequivalents of titratable acid per gram of catalyst,which is a unit used to describe acidity of the catalysts. Acidity isgenerally determined by titration with a base, as by adding excessivebase, such as sodium hydroxide, to the catalyst and then back titratingthe catalyst.

"Conv." and "Conversion" mean the mole percentage of a given reactantconverted to product. Generally, olefin conversion is about 95 percentor more in the practice of this invention.

"Sel." and "Selectivity" mean the mole percentage of a particularcomponent in the product. Generally, selectivity to the 2-phenyl isomeris about 70 or more in the practice of this invention.

The mordenite catalyst of the present invention is useful as a catalystin the production of LAB's in accordance with the process ofmanufacturing LAB's of this invention. LAB is useful as startingmaterial to produce sulfonated LAB, which itself is useful as asurfactant.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a representation of a first continuous reactivedistillation column employed in the practice of this invention.

FIG. 2 shows a representation of a second continuous reactivedistillation column employed in the practice of this invention.

FIG. 3 shows a representative process scheme for one embodiment of thisinvention where a conventional LAB alkylation reactor is shown incombination with a fluorine-containing mordenite reactor of thisinvention wherein a slip stream of reactant to the conventional reactoris sent to the mordenite reactor and wherein the flow of high 2-phenylisomer LAB from the mordenite reactor may be adjusted to vary the2-phenyl isomer LAB content of the effluent from the conventional LABalkylation reactor.

FIG. 4 shows another representative process scheme for one embodiment ofthis invention where a first conventional LAB alkylation reactor isshown in combination with a fluorine-containing mordenite reactors ofthis invention wherein a slip stream of reactant to the conventionalreactor is sent to one or both of a pair of mordenite reactor andwherein the effluent from the first LAB alkylation reactor and theeffluent from the one or both mordenite reactors are combined and flowedinto a second conventional LAB alkylation reactor.

DETAILED DESCRIPTION OF THE INVENTION Catalyst Preparation andProperties

The catalyst of this invention is a fluorine-containing mordenite.Mordenite is a type of zeolite. The catalyst of this invention isprepared from hydrogen mordenite (typically having 0.1 percent or lessof sodium) having a silica-alumina molar ratio of from about 10:1 toabout 100:1. More typically, the starting mordenite has a silica/aluminamolar ratio of from about 10:1 to about 50:1. The starting hydrogenmordenite, which is commonly available commercially, is treated with anaqueous solution of hydrogen fluoride ("HF") to produce the active,long-life and highly selective catalyst of the invention. In the courseof such HF treatment, as well as during subsequent calcination of saidHF-treated mordenite, the silica/alumina molar ratio typicallyincreases. The finished catalysts of this invention show a fluorinecontent of from about 0.1 to about 4 percent by weight, more typicallyabout 1 percent.

While not wishing to be bound by theory, it is believed that the HFreacts with sites where--Si--O--Al-- linkages occur such that thelinkage is broken with fluorine becoming bonded to the Al such that--Si--OH and F--Al-- groups form. This is believed to decrease the totalBronsted acid sites and increase the strength of the remaining acidsites in the mordenite and is believed to stabilize the acidity of themordenite such that the mechanisms which degrade performance during LABproduction, such as coke build-up, are retarded.

The aqueous solution used to treat the mordenite may contain a range ofHF concentrations. Generally, the HF concentration is a minimum of about0.1 percent by weight. Below such minimum concentration, the effect ofthe fluorine treatment significantly decreases, resulting in theundesirable need for repeated treatments. Generally, the HFconcentration on the upper end is about 10 percent by weight or less.Above a concentration of about 10 percent by weight, the HF is soconcentrated that it is difficult to prevent HF from destroying thecrystallinity of the mordenite, thereby detrimentally affecting itsefficacy as a catalyst for LAB production.

The aqueous HF solution may be prepared by diluting commerciallyavailable 48% HF solutions to the desired concentration. Alternatively,HF can be sparged into water to provide an aqueous HF solution.

Typically, the treatment is carried out by adding mordenite powder orpellets to a stirred aqueous HF solution at a temperature of from about0° C. to about 50° C. The stirring and contacting is continued for atime sufficient to achieve the desired level of fluorine in themordenite. This time may vary depending on factors such as HFconcentration, amount of HF solution relative to the amount of mordenitebeing treated, speed of agitation is employed, and temperature. Aftertreatment, the mordenite can be recovered by filtration, and then dried.It is also possible to impregnate the mordenite to incipient wetnesswith a given HF solution, as well as to treat the mordenite with gaseoushydrogen fluoride. Preferably said fluoride-treated mordenite would becalcined in air prior to use in alkylation service. The preferredcalcination temperature would be in the range from about 400° C. toabout 600° C. Alternative mordenite fluorinating agents to hydrofluoricacid and hydrogen fluoride include ammonium fluoride, fluorided siliconcompounds and fluorided hydrocarbons.

The HF-treated mordenite of this invention generally has about 0.1percent by weight or more of fluorine based on the total weight of themordenite. Typically, the fluorine-containing mordenite contains about 4percent by weight or less fluorine. The fluorine-containing mordenitemost typically contains about 1 percent by weight of fluorine.

The mordenite can be used in the practice of this invention as a powder,in pellet form, as granules, or as extrudates. The mordenite can beformed into pellets or extrudates using binders well known to those ofskill in the art, such as alumina, silica or mixtures thereof.

Reactants for LAB Production

In the practice of this invention, benzene is alkylated with olefin toform LAB. These reactants can be handled and purified as is generallyperformed by those of skill in the art. In this regard, it is preferredthat the reactants are water and alcohol free. The olefins employed inthe practice of this invention have from about 8 to about 30 carbons,preferably from about 10 to about 14 carbons, such as is availablecommercially or produced as dehydrogenated paraffin feed stocks. It ispreferred that the olefin be monounsaturated. It is most preferred thatthe olefin be an alpha-olefin containing a terminal ethylenic unit.

Commonly, said olefins would be available in a paraffini media of thesame carbon range. Olefins in the 10 to 14 carbon number range wouldtypically be available from C₋₁₀ to C₋₁₄ paraffin dehydrogenation in aC₋₁₀ to C₋₁₄ paraffin mixture having an olefin content of 5 to 20%.Often, the olefin content of said paraffin-olefin mixture would be 8 to10 weight %.

The 2-phenyl isomer of the LAB produced in accordance with thisinvention is of formula: ##STR1## wherein n is from about 5 to about 17and preferably from about 7 to about 11.

Process Conditions, Procedures, and Apparatus

The process of this invention can be carried out using the continuousreactive distillation column depicted in FIG. 1. In FIG. 1, a feedmixture of benzene and olefin, generally at a benzene-to-olefin molarratio range of about 1:1 to 100:1 flows from feed pump 10 to feed inlet14 via line 12. The feed mixture falls to packed mordenite catalyst bed32 where alkylation in the presence of the fluorine-containing mordeniteoccurs. Alternatively, while not depicted in FIG. 1, the benzene andolefin can be introduced separately into the bed with mixing occurringin the bed, or the reactants can be mixed via an in-line mixer prior tointroducing the reactants into the catalyst bed, or the reactants can beinjected separately above the bed with mixing affected by use ofstandard packing above the bed, or the reactants can be sparged into thechamber above the bed. The catalyst bed 32 depicted in FIG. 1 forlaboratory scale may be made of two lengths of 1.1 inch internaldiameter tubing, the lengths being 9.5 inches and 22 inches. In thecatalyst bed 32, the falling feed mixture also contacts rising vapors ofunreacted benzene which has been heated to reflux in reboiler 42 byheater 40. Such rising vapors pass over thermocouple 38 which monitorstemperature to provide feedback to heater 40. The rising vapors ofbenzene and/or olefin also pass through standard packing 36 (e.g., 7.5inches of goodloe packing). The rising vapors heat thermocouple 30 whichconnects to bottoms temperature controller 28 which activates heater 40when temperature drops below a set level.

Prior to startup, the system may be flushed with nitrogen which entersvia line 54 and which flows through line 58. After startup, a nitrogenblanket is maintained over the system. Also prior to startup and duringnitrogen flush, it may be desirable to heat catalyst bed 32 so as todrive off water from the fluorine-containing mordenite.

Residual water from the feed mixture or which otherwise enters thesystem is collected in water trap 24 upon being liquefied at condenser21 (along with benzene vapor). If the feed is very dry (free of water)the water trap 24 may not be needed. Removing water leads to longercatalyst lifetime. Hence, the water trap 24 is optional. The sameapplies to FIG. 2. Condenser 21 is cooled via coolant such as waterentering condenser 21 via port 22 and exiting via port 20. As needed,water in water trap 24 may be drained by opening drain valve 26.

As needed, when LAB content in reboiler 42 rises to a desired level, thebottoms LAB product may be removed from the system via line 47, usingeither gravity or bottoms pump 48 to withdraw the product. When productis so withdrawn, valve 44 is opened.

In FIG. 1, dip tube 46, which is optional, is employed to slightlyincrease the pressure in reboiler 42 to thereby raise the boiling pointof benzene a degree or two. Likewise, a pressure generator 56 may beoptionally employed to raise the pressure of the system. Other standardpressure increasing devices can be employed. Pressure cam thus beincreased in the system such that the boiling point of benzene increasesup to about 200° C.

In FIG. 1, control mechanisms for heat shutoff 50 and pump shutoff 52are depicted which serve to shut off heat and pump if the liquids levelin the system rises to such levels. These control mechanisms areoptional and may be included so that the catalyst bed does not come intocontact with the bottoms of the reboiler. Line 60 connects pump shutoff52 to the system above condenser 21.

In the practice of this invention in the alkylation of benzene, a widevariety of process conditions can be employed. In this regard, thetemperature in the catalyst bed may vary depending on reactants, rate ofintroduction into the catalyst bed, size of the bed, and so forth.Generally, the bed is maintained at the reflux temperature of benzenedepending on pressure. Typically, the temperature of the catalyst bed isabove about 70° C., and most likely about 78° C. or more in order tohave reasonable reaction rates, and about 200° C. or less to avoiddegradation of reactants and products and to avoid deactivation of thecatalyst by coke build-up. Preferably, the temperature is in the rangefrom about 80° C. to about 140° C. The process may be operated at avariety of pressures during the contacting step, with pressures of aboutatmospheric most typically being employed. When the process is operatedusing a system as depicted in FIGS. 1 and 2, the reboiler temperature ismaintained such that benzene and olefin vaporize, the temperaturevarying depending on olefin, and generally being from about 80° C. toabout 250° C. for olefins having 10 to 14 carbons. The composition ofthe reboiler will vary over time, but is generally set initially to havea benzene olefin ratio of about 5:1, with this ratio being maintainedduring the practice of this invention. The rate of introduction of feedinto the catalyst bed may vary, and is generally at a liquid hourlyspace velocity ("LHSV") of about 0.05 hr⁻¹ to about 10 hr⁻¹, moretypically from about 0.05 hr⁻¹ to about 1 hr⁻¹. The mole ratio ofbenzene to olefin introduced into the catalyst bed is generally fromabout 1:1 to about 100:1. In commercial benzene alkylation operations,it is common to run at mole ratios of from about 2:1 to about 20:1,which can suitably be employed in the practice of this invention, and tocharge said olefins as an paraffin-olefin mixture comprising 5% to 20%olefin content. Said paraffin-olefin mixtures are normally generatedcommercially through dehydrogenation of the corresponding paraffinstarting material over a noble metal catalyst.

Another continuous reactive distillation apparatus is depicted in FIG.2. In FIG. 2, the feed mixture enters the reactor via feed inlet 114.The feed mixture falls through the column into catalyst bed 132, whereinalkylation to form LAB occurs. A thermowell 133 monitors the temperatureof said catalyst bed 132. The catalyst bed 132 may be optionally heatedexternally and is contained within 11/4 inch stainless steel tubing.Goodloe packing is positioned at packing 136 and 137. LAB product, aswell as unreacted benzene and olefin, fall through packing 136 intoreboiler 142. In reboiler 142, electric heater 140 heats the contents ofreboiler 142 such that heated vapors of benzene and olefin rise from thereboiler 142 to at least reach catalyst bed 132. As needed, the bottomsLAB product may be removed from reboiler 142 by opening bottoms valve144 after passing through line 147 and filter 145. Residual water fromthe feed mixture, or which otherwise enters the system, may be condensedat condenser 121 which is cooled with coolant via outlet line 122 andinlet line 120. The condensed water falls to water trap 124, which canbe drained as needed by opening drain valve 126. Temperature in thesystem is monitored via thermocouples 138, 130, and 165. The systemincludes pressure release valve 166. A nitrogen blanket over the systemis maintained by introduction of nitrogen gas via inlet line 154. Levelcontrol activator 150 activates bottoms level control valve 151 to openwhen the liquids level in the reboiler rises to the level controlactivator 150. Line 160 connects level control activator 150 to thesystem above condenser 121.

While the systems depicted in FIG. 1 and FIG. 2 show single catalyst bedsystems, it may be appreciated that multi-catalyst bed reactors arewithin the scope of this invention, as well as multiple ports for inletfeeds, water traps, product removal lines, and so forth. Moreover, theprocess may be run in batch mode, or in other continuous processes usingplugflow designs, trickle bed designs, and fluidized bed designs.

It is believed that as average molecular weight of olefins increases,particularly when the average number of carbons exceed 14, theselectivity and conversion to LAB, especially LAB with the 2-isomer, mayincrementally decrease. If desired, the product of the alkylation usingHF-treated mordenite may be sent to a second, finishing catalyst bed toimprove yield. This procedure is optional and is believed to bedependent on the needs and desires of the end user. An example of such asecond catalyst is HF-treated clay such as montmorillonite clay havingabout 0.5% fluoride. Such a catalyst may also serve to lower the brominenumber below about 0.1, depending on conditions.

Variable 2-phenyl Isomer Content of Product Using the Mordenite of thisInvention in Combination with Conventional LAB Alkylation

The fluorine-containing mordenite of this invention generally producesLAB having high 2-phenyl isomer content, such as higher than about 70%.Currently, LAB purchasers who make detergents would prefer to use LABhaving a 2-phenyl isomer content in the range from about 30 to about 40percent, but this level is not available in the marketplace.Conventional LAB alkylation technology do not achieve these higher2-phenyl isomer levels. HF, which is currently the most widely usedcatalyst for production of LAB on a commercial scale, produces about16-18 percent of the 2-phenyl isomer in the product stream from thereactor. Aluminum chloride, in contrast, produces about 26-28 percent ofthe 2-phenyl isomer. The present inventors recognized that a need existsfor a process which produces a 2-phenyl isomer product in the desiredrange.

It has now been found that the mordenite of this invention can be usedin combination with conventional LAB alkylation catalysts, such as HFand aluminum chloride alkylation catalysts. This may be affected bywithdrawing a slip stream of reactant that is being sent to theconventional LAB reactor, and directing the slip stream to the mordenitereactor. Since conventional LAB catalysts produce product having a2-phenyl isomer content much less than that from mordenite of thisinvention, combining the products from each catalyst results in aproduct having a higher 2-phenyl isomer content than that from theconventional LAB alkylation catalyst. For example, while the catalyst ofthis invention typically produces a 2-phenyl isomer content of 70% ormore, a typical HF process produces about 16-18% of the 2-phenyl isomer.By combining effluent from each catalyst at given proportions, theresulting mixture will have any desired 2-phenyl isomer content in therange between the 2-phenyl isomer contents of the HF catalyst productand the mordenite catalyst product. Thus, the levels of 2-phenyl isomermay be adjusted by the amount of reactants sent to the mordenitecatalyst and/or by storing 2-phenyl isomer product from the mordenitecatalyst for later mixing with the product of from the conventional LABalkylation catalyst to thereby achieve any desired level of 2-phenylisomer content in the final product. An advantage of this inventionpertains to the ability to retrofit an existing, conventional LAB systemwith a reactor containing fluorine-treated mordenite of this invention.This enables existing users of the conventional LAB technology toaugment their existing facilities without interrupting their production.This provides a considerable cost advantage to the producer.

The conventional LAB catalysts used most frequently are HF alkylationreactors and aluminum chloride alkylation catalysts. Other alkylationcatalysts include various zeolites, alumina-silica, various clays, aswell as other catalysts.

FIG. 3 depicts a representative, non-limiting scheme for practice ofthis invention wherein the fluorine-treated mordenite is used incombination with a HF alkylation reactor to afford LAB having high2-phenyl isomer contents relative to that produced from the HF reactoralone. The scheme of FIG. 3 is shown in the context of LAB alkylationbased on a feed from a paraffin dehydrogenation facility. Prior to thisinvention, the plant depicted in FIG. 3 would be operated conventionallywithout use of mordenite reactor 220.

Thus, in conventional operation, fresh paraffin is fed to conventionaldehydrogenation apparatus 210 via line 211, with recycled paraffin beingintroduced from the paraffin column 250 via line 252. Dehydrogenatedparaffin from the dehydrogenation apparatus 210 is then pumped into aconventional alkylation reactor 230 containing conventional LABcatalyst, such as HF, via conduit 214. The dehydrogenated paraffin feedmay of course be supplied from any provider. The source ofdehydrogenated paraffin (olefin) is not critical to the practice of thisinvention. LAB product from alkylation unit 230 may thereafter bepurified by a series of distillation towers.

In this regard, alkylation effluent is delivered to a benzene column 240by way of line 231. It should be appreciated that the alkylation productmay be sent offsite for purification. Further, the particularpurification scheme used is not critical to the practice of thisinvention, but is depicted in FIG. 3 as representative of a typicalcommercial operation. In FIG. 3, unreacted benzene is distilled off fromthe crude LAB product. Benzene is then recycled to the alkylationreactor 230. The benzene-free LAB crude product from the benzene column240 is pumped through line 241 to olefin column 250 where any olefinpresent is distilled off, with the distilled olefin being recycled toparaffin dehydrogenation unit 210 via line 252. Olefin-free crude LABalkylate from the olefin column 250 is transported to a refining column260 where purified LAB is distilled and removed via line 262. Heavies(e.g., dialkylates and olefin derivatives) are withdrawn from refiningcolumn 260 via conduit 261.

In the practice of this invention, a fluorine-treated mordenitecontaining reactor 220 is used in conjunction with the conventionalalkylation reactor 230. In the embodiment of this invention depicted inFIG. 3, a slip stream of benzene/dehydrogenated paraffin feed is takenfrom line 214 and pumped through mordenite reactor 220 where high2-phenyl isomer production is achieved. LAB product from reactor 220,high in 2-phenyl isomer, is then introduced back into line 214 via line222. Alternatively mordenite reactor 220 may be fed benzene anddehydrogenated paraffin (olefin) directly, rather than by way of a slipstream from line 221. In addition, effluent from reactor 220 may, in thealternative if no unreacted olefin is present, be sent directly tobenzene column 240, for later combination with conventional alkylationreactor 230 product or transported and tied into conduit 231, whichfeeds benzene column 240. It should be appreciated that columns 240,250, and 260 may be maintained at conditions (e.g., pressure andtemperature) well known to those of skill in the art and may be packedwith conventional materials if desired.

FIG. 4 depicts an alternative configuration to that shown in FIG. 3. InFIG. 4, dual mordenite beds 320, 321 are used in conjunction withconventional alkylation reactors 330, 340. Conveniently, one of themordenite reactors may be in operation while the other reactor is downfor catalyst regeneration. For example, during operation, olefin feed(dehydrogenated paraffin) is supplied via line 301, with benzene orother aromatic feed stock being provided via line 302. The admixedreactants may flow to standard alkylation reactor 330 via line 304bafter passing through heat exchanger 303. A portion of the mixed streammay be withdrawn via line 304a for supply to the mordenite reactor. Theextent of the mixed feed stream being withdrawn may be varied dependingon the desired level of 2-phenyl isomer in the final product. In anotherembodiment, the product from the reactor containing mordenite 320, 321may be fed to the first alkylation reactor 330, particularly if thesecond alkylation reactor 34 is not employed in the process.

The slip stream reactants may optionally be sent to dewatering unit 317by application of pump 306 after passing through heat exchanger 305. Inthe dewatering unit 317, water is distilled from the reactants indewatering tower 310. Rising vapor exits via line 311a and passesthrough heat exchanger 312 wherein condensation occurs. Effluent fromheat exchanger 312 is advanced to water trap 318 via line 311b. Water isremoved from water trap 318 via line 313, with the bottom organic layerbeing returned to the dewatering tower 310. Dewatered reactants may beremoved via line 316 and conveyed to either line 316a or line 316b. Someof the dewatered reactant may be withdrawn by conduit 314b, sent throughheat exchanger 315 and returned to the tower 310 via line 314a. In thisregard, heat exchanger 315 may serve as a reboiler.

After reaction in either reactor 320 or 321, LAB product is sent tolines 322 and 331 from either line 322a or 322b after passing throughheat exchanger 323. When desired, one of the catalyst beds may beregenerated, as by calcination for example, through use of regenerationheater 350, which may be connected to the reactor of choice by dottedline 351 through valving and hardware that are not shown. The reactors320 and 321 may optionally be run simultaneously. The reactors 320 and321 may be loaded with mordenite catalyst in any fashion, as would beapparent to one of skill in the art. Typically, a plugged flowarrangement is used. The amount of catalyst employed may vary dependingon a variety of considerations such as type and flow rate of reactants,temperature and other variables. The combined effluents fromconventional reactor 330 and mordenite reactors 320 or 321 may be fed toa second conventional reactor 340, or optionally may be sent to apurification section directly if no unreacted paraffin is present (theconventional reactor serves to complete reaction of any paraffin that isnot converted in the mordenite reactors 320, 321). In FIG. 4, effluentfrom the second conventional alkylation reactor is advanced to apurification section. The second alkylation reactor may be used to reactunreacted feed stock from reactors 330, 320 and 321 to thereby reducerecycle loads.

It should be appreciated that a wide variety of configurations arecontemplated, and the figures should not be construed as limiting thisinvention or claims hereto. Additional reactors and other equipment may,for example, be used.

The following examples are illustrative of the present invention and arenot intended to be construed as limiting the scope of the invention orthe claims. Unless otherwise indicated, all percentages are by weight.In the examples, all reactants were commercial grades and used asreceived. The apparatus depicted in FIG. 1 was employed for examples2-4. The apparatus depicted in FIG. 1 was used for example 5.

It may be noted that example 2 illustrates LAB production from paraffindehydrogenate using the fluoride-treated mordenite catalyst of exampleB, where good catalyst life (250+ hrs) is achieved without catalystregeneration, while maintaining a 2-phenyl LAB selectivity of >70% andhigh LAB productivity without significant loss of fluoride. Comparativeexample 1, on the other hand, using untreated mordenite, with nofluoride added, shows a rapid decline in LAB production. In addition,examples 3 and 4 illustrate LAB production using a 5:1 molar benzene/C₁₀-C₁₄ olefin feed mix and the fluoride-treated mordenite catalysts ofExample B when operating at different LHSV's in the range of 0.2-0.4hr⁻¹. Catalyst life may exceed 500 hours. Example 5 illustrates LABproduction with the fluoride-treated mordenite catalyst where thealkylation is conducted at higher temperatures and under pressure.Examples 6-8 illustrate the performance of three HF-treated mordenitecatalysts with different fluoride loadings. Example 9 shows howvirtually no alkylation activity is observed with a highly-fluorinatedmordenite.

EXAMPLE A

This example illustrates the preparation of a hydrogen fluoride-modifiedmordenite.

To 30 g of acidified mordenite (LZM-8, SiO₂ /Al₂ O₃ ratio 17; Na₂ O wt %0.02, surface area 517 m² /g, powder, from Union Carbide Corp.) wasadded 600 ml of 0.4% hydrofluoric acid solution, at room temperature.After 5 hours the solid zeolite was removed by filtration, washed withdistilled water, dried at 120° C. overnight, and calcined at 538° C.

EXAMPLE B

The example illustrates the preparation of a hydrogen fluoride-modifiedmordenite.

To 500 g of acidified, dealuminized, mordenite (CBV-20A from PQ Corp.;SiO₂ /Al₂ O₃ molar ratio 20; Na₂ O, 0.02 wt %; surface area 550 m² /g,1/16" diameter, extrudates, that had been calcined at 538° C.,overnight) was added a solution of 33 ml of 48% HF solution in 1633 mlof distilled water, the mix was cooled in ice, stirred on a rotaryevaporator overnight, then filtered to recover the extruded solids. Theextrudates were further washed with distilled water, dried in vacuo at100° C., and then calcined at 538° C., overnight.

Analyses of the treated mordenite showed:

    ______________________________________                                               F:           1.2%                                                        Acidity: 0.49 meq/g                                                         ______________________________________                                    

EXAMPLE 1

This example illustrates the preparation of linear alkylbenzenes using ahydrogen fluoride-modified mordenite catalyst.

To a 500 ml flask, fitted with condenser and Dean Stark Trap was added100 ml of benzene (reagent grade) plus 10 g of hydrogenfluoride-modified mordenite zeolite, prepared by the method of ExampleA. The mix was refluxed for 15-20 minutes to remove small amounts ofmoisture, then a combination of benzene (50 ml) plus 1-dodecene (10 g)was injected into the flask and the solution allowed to reflux for 3hours.

Upon cooling, the modified mordenite catalyst was removed by filtration,the filtrate liquid flashed to remove unreacted benzene, and the bottomsliquid analyzed by gas chromatography.

Typical analytical data are summarized in Table 1.

                  TABLE 1                                                         ______________________________________                                        DODE-                                                                           CENE  LINEAR                                                                CONV. LAB ISOMER DISTRIBUTION (%)                                                                       HEAVIES  LAB                                        (%)   2-Ph   3-Ph   4-Ph  5-Ph 6-Ph (%)    (LLAB) (%)                         ______________________________________                                        99.7  79.9   16.6   0.8   1.3  1.3  0.2    95.9                               ______________________________________                                    

EXAMPLE 2

This example illustrates the preparation of linear alkylbenzenes fromparaffin dehydrogenate using a hydrogen fluoride-treated mordenitecatalyst.

In the example, benzene was alkylated with a sample of C₁₀ -C₁₄ paraffindehydrogenate containing about 8.5% C₁₀ -C₁₄ olefins. Alkylation wasconducted in a process unit as shown in FIG. 1.

Alkylation was conducted by first charging 500 ml of a benzene/paraffindehydrogenate mix (10:1 molar ratio, benzene/C₁₀ -C₁₄ olefin) to thereboiler and 250 cc of the HF-treated mordenite of example B to the 1.1"i.d. reaction zone. The mordenite was held in place using Goodloepacking. The reboiler liquid was then heated to reflux and a benzeneplus C₁₀ -C₁₄ paraffin dehydrogenate mix (10:1 molar ratio, benzene/C₁₀-C₁₄ olefin) continuously introduced into the unit above the catalystcolumn at the rate of 100 cc/hr. (LHSV=0.4 hr⁻¹).

Under steady state, reflux, conditions liquid product was continuouslywithdrawn from the reboiler and water continuously taken off from thewater trap. The crude liquid product was periodically analyzed by gaschromatography. The reboiler temperature was typically in the controlledrange of 97-122° C. The column head temperature variability was 78-83°C. A summary of the analytical results may be found in Table 2.

After 253 hours on stream, the recovered HF-treated mordenite catalystshowed by analysis:

    ______________________________________                                               F:           1.1%                                                        Acidity: 0.29 meq/g                                                           H.sub.2 O: 0.3%                                                             ______________________________________                                    

                  TABLE 2                                                         ______________________________________                                        Time on          Alkylate  2-Phenyl                                             Stream (Hrs) Sample Conc. (%) Sel. (%) C                                                                      .sub.6 H.sub.6 Conc. (%)                    ______________________________________                                        0        0       1.4              32.3                                          2 1 3.4  19.7                                                                 4 2 5.8 74.9 16.6                                                             6 3 6.6 75.8 25.2                                                             32 4 7.9 80.7 27.0                                                            56 5 7.8 82.7 27.0                                                            69 6 7.3 81.4 27.4                                                            94 7 6.5 82.0 27.8                                                            118 8 6.0 78.4 27.7                                                           142 9 5.9 81.3 26.9                                                           166 10 5.4 81.5 27.3                                                          207 11 5.3 81.3 26.1                                                          229 12 5.1 81.1 27.4                                                          253 13 4.9 81.4 28.1                                                        ______________________________________                                    

Comparative Example 1

This example illustrates the preparation of linear alkylbenzene fromparaffin dehydrogenate using an untreated mordenite catalyst.

Following the procedures of Example 9, the alkylation unit was chargedwith 250 cc of untreated, calcined, mordenite, (the starting mordeniteof Example B), and the liquid feed comprised benzene plus C₁₀ -C₁₄paraffin dehydrogenate mix in a 10:1 molar ratio of benzene/C₁₀ -C₁₄olefin.

Typical results are summarized in Table 3.

The recovered mordenite showed by analysis:

    ______________________________________                                               Acidity:     0.29 meq/g                                                  H.sub.2 O: 2.1%                                                             ______________________________________                                    

                  TABLE 3                                                         ______________________________________                                        Time on          Alkylate  2-Phenyl                                             Stream (Hrs) Sample Conc. (%) Sel. (%) C                                                                      .sub.6 H.sub.6 Conc. (%)                    ______________________________________                                        0        0                        11.2                                          2 1 6.50  9.9                                                                 4 2 7.16 73.2 17.1                                                            6 3 7.09 73.1 26.4                                                            22 4 8.61 73.9 26.6                                                           31 5 10.49 67.4 15.8                                                          46 6 7.39 75.0 27.7                                                           70 7 6.39 75.1 28.5                                                           93 8 6.08 73.6 23.0                                                           144 9 5.21 73.6 15.8                                                          157 10 4.40 73.9 26.2                                                         180 11 3.06 69.6 27.1                                                         204 12 1.32  19.5                                                             228 13 1.32  33.3                                                           ______________________________________                                    

EXAMPLE 3

This example also illustrates the preparation of linear alkylbenzenefrom paraffin dehydrogenate using a hydrogen fluoride-treated mordenitecatalyst.

Following the procedures of Example 2, the alkylation unit was chargedwith 250 cc of the HF-treated mordenite of Example B, and the liquidfeed comprised a benzene plus C₁₀ -C₁₄ paraffin dehydrogenate mix in a5:1 molar ratio of benzene/C₁₀ -C₁₄ olefin, the reboiler temperature wastypically in the range of 122-188° C., the column head temperature78-83° C. Typical analytical results are summarized in Table 4.

After 503 hours on stream, the recovered HF-treated mordenite catalystshowed on analysis:

    ______________________________________                                               F:           1.0%                                                        Acidity: 0.35 meq/g                                                           H.sub.2 O: 0.1%                                                             ______________________________________                                    

                  TABLE 4                                                         ______________________________________                                                                               Corrected.sup.a                          Time on  Alkylate 2-Phenyl C.sub.6 H.sub.6 Alkylate                           Stream (Hrs) Sample Conc. (%) Sel. (%) Conc. (%) Conc. (%)                  ______________________________________                                        0        0      1.0             8.9    1.1                                      2  1 3.5 61.8 0.3 3.5                                                         4  2 7.1 72.1 0 7.1                                                           6  3 6.8 76.7 7.2 7.3                                                         34  4 8.4 79.7 14.3 9.8                                                       71  5 7.2 81.8 14.6 8.5                                                       96  6 6.5 80.8 15.5 7.7                                                       119  7 6.3 80.6 15.1 7.4                                                      643  8 6.0 81.0 14.3 7.0                                                      168  9 5.9 80.7 14.4 6.9                                                      239 10 5.0 78.2 8.8 5.5                                                       263 11 5.3 79.2 13.5 6.2                                                      288 12 5.0 79.6 16.5 6.0                                                      311 13 5.4 79.4 4.1 5.6                                                       335 14 5.5 79.2 8.2 6.0                                                       408 15 4.9 79.4 13.1 5.6                                                      432 16 4.7 78.8 14.4 5.5                                                      456 17 4.4 78.5 14.1 5.1                                                      479 18.sup.a 4.7 78.6 2.7.sup.b 4.8                                           488 19.sup.b 4.9 78.5 2.4.sup.c 5.0                                           503 20.sup.b 5.1 78.9 0.6.sup.c 5.1                                         ______________________________________                                         .sup.a Corrected for benzene in effluent sample.                              .sup.b Applied pressure 8" H.sub.2 O                                          .sup.c Applied pressure 12" H.sub.2 O                                    

EXAMPLE 4

This example also illustrates the preparation of linear alkylbenzenesfrom paraffin dehydrogenate using a hydrogen fluoride-treated mordenitecatalyst.

Following the procedures of Example 2, alkylation was conducted in theglassware unit of FIG. 1 complete with catalyst column, reboiler,condenser and controls. To the reaction zone was charged 500 cc ofHF-treated mordenite of Example B. The liquid feed comprised a benzeneplus C₁₀ -C₁₄ paraffin dehydrogenate mix in a 5:1 molar ratio of benzene/C₁₀ -C₁₄ olefin. The feed rate was 100 cc/hr (LHSV:0.2 hr⁻¹).

Under typical steady state, reflux, conditions, with a reboilertemperature range of 131-205° C. and a head temperature of 76-83° C.,typical results are summarized in Table 5.

                                      TABLE 5                                     __________________________________________________________________________    Pressure  Time on  Alkylate        Corrected.sup.a                              (Inch Reboiler Stream  Conc. 2-Phenyl C.sub.6 H.sub.6 Conc. Alkylate                                            H.sub.2 O) Temp. (C.) (Hrs) Sample                                           (%) Sel. (%) (%) Conc. (%)                 __________________________________________________________________________    12  205    2   1   8.2  74.3 0.5   8.3                                           193  4 2 9.2 75.0 0.4 9.2                                                     175  6 3 10.0 74.8 2.3 10.3                                                   204  21 4 12.7 78.7 0.3 12.7                                                  146  44 5 11.7 81.0 10.4 12.9                                                 136  68 6 11.5 81.8 10.0 12.7                                                  2-3 days C.sup.b 11.6 81.4 9.4 12.7                                          136  93 7 11.3 82.6 10.8 12.5                                                  4-5 days C-1.sup.b 11.0 81.8 11.0 12.2                                       142 165 8 10.4 83.0 11.4 11.5                                                 142 189 9 10.2 83.4 10.5 11.2                                                 146 213 10  9.7 80.2 11.2 10.7                                                139 238 11  9.6 83.4 11.1 10.7                                                143 261 12  9.9 81.9 11.0 11.0                                                133 333 13  9.2 83.4 11.3 10.3                                                138 356 14  8.9 83.5 11.1 9.9                                                 138 381 15  8.8 83.0 11.3 9.8                                                 131 405 16  8.7 82.8 11.2 9.7                                              __________________________________________________________________________     .sup.a Corrected for benzene in effluent sample                               .sup.b Composite product                                                 

EXAMPLE 5

This example illustrates the preparation of linear alkylbenzenes fromparaffin dehydrogenate using a hydrogen fluoride-treated mordenitecatalyst.

Following the procedures of Example 2, alkylation of benzene with C₁₀-C₁₄ paraffin dehydrogenate was conducted using the stainless-steel unitof FIG. 2, complete with catalyst column, reboiler, condenser, andcontrols. About 250 cc or HF-treated mordenite of Example B was chargedto the column. The liquid feed comprised benzene plus C₁₀ -C₁₄ paraffindehydrogenate mix in a 10:1 molar ratio of benzene/C₁₀ -C₁₄ olefin. TheLHSV varied from 0.2 to 0.4 hr⁻¹.

Alkylation was conducted over a range of column and reboilertemperatures and a range of exit pressures. Typical results aresummarized in Table 6.

                                      TABLE 6                                     __________________________________________________________________________    Pressure   Pot        Alkylate                                                Column                                                                             DIFF                                                                             EXIT                                                                             Temp.                                                                             Time                                                                             Sample                                                                            Conc.                                                                              2-Phenyl                                                                           C.sub.6 H.sub.6 Conc.                           Temp (C.) (psi) (psi) (C.) (hr) (#) (%) Sel. (%) (%)                        __________________________________________________________________________    149-129                                                                            0.1                                                                              0  188  4  1  3.8       6.3                                             152-126 0 0 200 20  2 1.8  32.7                                               195-108 0 0 199 25  3 5.7  8.7                                                218-111 0 0 201 28  4 0.8  67.5                                               212-118 0 0 201 44  5 8.8 71.7 4.5                                            209-114 0.2 0 198 52  6 2.4  47.3                                             228-116 0 0 197 68  7 6.9 72.6 12.4                                           187-107 0.5 0 197 76  8 2.9 74.6 44.1                                             76 .sup.  9.sup.a 4.8 72.9 25.3                                                9C.sup.b 6.8 72.2 1.0                                                    174-107 0 0 178  6 10 4.1 79.2 54.9                                           170-106 0 0 172 22 11 2.0  59.8                                                   28 .sup. 12.sup.a 6.6 76.8 26.8                                           142-107 0 0 136 31 13 4.8 67.9 18.9                                           141-110 0 0 138 47 14 4.4 65.9 16.9                                           142-110 0 0 136 55 15 5.0 63.9 16.6                                           168-111 0 0 131 71 16 4.1 64.8 16.7                                           170-108 0 0 150 79 17 5.0 72.0 8.8                                            175-113 0 0 143 95 18 5.9 68.1 15.2                                           145-106 0 5.2 188 14 19 3.2 60.2 9.0                                          149-108 0 4.2 186 20 20 4.8 66.3 12.0                                         160-118 0 11.7 213 29 21 4.2  6.7                                             160-119 0 9.3 210 44 22 5.2  6.6                                            __________________________________________________________________________     .sup.a Composite product                                                      .sup.b Stripped composite product                                        

EXAMPLES 6-8

These examples illustrate the preparation of linear alkylbenzene usinghydrogen fluoride-modified mordenite catalysts with different fluoridetreatment levels.

Following the procedures of Example 1, the alkylation unit was chargedwith benzene (100 ml), a 10 g sample of hydrogen fluoride-modifiedmordenite prepared by the procedure of Example B, plus a mix of benzene(50 ml) and 1-decene (10 g). Three HF-treated mordenites were tested,having the composition:

Catalyst "C" 0.25% HF on mordenite (CBV-20A)

Catalyst "D" 0.50% HF on mordenite (CBV-20A)

Catalyst "E" 1.0% HF on mordenite (CBV-20A)

In each experiment samples of the bottoms liquid fraction were withdrawnat regular periods and subject to gas chromatography analyses. Theresults are summarized in Table 7.

                                      TABLE 7                                     __________________________________________________________________________    CATALYST                                                                            TIME                                                                              %LLAB                                                                              %ISOS                                                                             %HVY                                                                              %2Ph                                                                              %3Ph                                                                             %4Ph                                                                             %5Ph                                                                             %6&7Ph                                    __________________________________________________________________________    D     10  11.75                                                                              0.14                                                                              0   73.36                                                                             21.87                                                                            2.89                                                                             0.94                                                                             1.02                                         20 12.43 0.21 0 72.97 21.96 3.14 1.13 0.81                                    30 12.88 0.21 0 72.67 22.13 3.03 1.16 1.01                                    40 12.27 0.22 0 73.02 21.92 2.85 1.06 1.14                                    50 12.15 0.98 0 72.46 21.67 3.21 1.17 1.49                                    50 12.24 1.01 0 72.53 21.63 3.23 1.12 1.44                                    60 12.28 0.21 0 72.96 22.07 2.93 1.14 0.91                                    60 11.98 0.21 0 72.97 22.21 2.93 1.17 0.83                                   C 10 12.2 0.18 0 72.54 22.46 3.21 0.98 0.82                                    20 12.7 0.39 0 71.51 22.61 2.91 1.02 2.13                                     30 12.52 0.21 0 71.96 22.68 2.96 1.04 1.36                                    40 12.75 0.21 0 71.84 22.67 3.22 1.02 1.25                                    50 12.98 0.21 0 71.57 22.81 3.16 1.08 1.39                                    60 12.54 0.21 0 71.45 22.81 3.19 1.12 1.44                                    60 12.33 0.21 0 71.61 22.87 2.92 1.05 1.31                                   E 10 10.56 0.05 0 75.19 19.41 2.18 3.22                                        20 12.95 0.15 0 74.36 19.23 3.01 3.4                                          30 13.44 0.18 0 74.11 19.42 3.2 3.27                                          40 13.16 0.15 0 074.16 19.38 3.12 3.34                                        50 13.1 0.15 0 74.43 19.16 3.21 3.28                                          60 12.83 0.15 0 74.28 19.49 2.88 3.35                                         60 12.87 0.16 0 73.82 19.97 2.8 3.2                                        __________________________________________________________________________

EXAMPLE 9

This example illustrates the inactivity of a heavily loadedhydrogen-fluoride modified mordenite catalyst.

Following the procedures of Example 2, the alkylation unit was chargedwith 100 cc of a hydrogen fluoride-treated mordenite (CBV-20A) preparedby the method of Example B but having a much higher loading of HF(fluoride content 4.8%). The acidity of said HF-treated mordenite was0.15 meq/g.

No significant amount of alkylated product was detected by gaschromatography.

What is claimed is:
 1. A process for the production of linearalkylbenzene, comprising:contacting benzene and an olefin having about 8to about 30 carbons in the presence of a fluorine-containing mordeniteto form a first linear alkylbenzene stream; contacting benzene and anolefin having about 8 to about 30 carbons in the presence of analkylation catalyst other than the fluorine-containing mordenite to forma second linear alkylbenzene stream; combining the first linearalkylbenzene stream and the second linear alkylbenzene stream to form athird linear alkylbenzene stream, wherein the mordenite has been treatedby contacting the mordenite with an aqueous hydrogen fluoride solution,wherein the hydrogen fluoride in the aqueous solution has aconcentration in the range from about 0.1 percent to about 1 percent byweight.
 2. The process of claim 1, wherein the olefin is obtained bydehydrogenating a paraffin.
 3. The process of claim 1, wherein the thirdlinear alkylbenzene stream is distilled to remove unreacted benzene,olefin and any components heavier than the linear alkylbenzene.
 4. Theprocess of claim 1, wherein the fluorine-containing mordenite has asilica to alumina molar ratio in a range from about 10:1 to about 50:1.5. The process of claim 1, wherein the benzene and olefin that iscontacted with mordenite is a slip stream from a stream containingbenzene and olefin that is to be contacted with the alkylation catalystother than the fluorine-containing mordenite.
 6. The process of claim 1which is operated under conditions effective to produce a 2-phenylisomer content in the third linear alkylbenzene stream in the range fromabout 30 to about 40 percent by weight.
 7. The process of claim 1,wherein the benzene and olefin to be contacted with the mordenite has abenzene/olefin ratio of from about 2:1 to about 20:1, wherein themordenite is maintained at a temperature in the range from about 70degrees Centigrade to about 200 degrees Centigrade, and wherein thebenzene and olefin that contacts the mordenite has a combined liquidhourly space velocity in the range from about 0.05 hr⁻¹ to about 10hr⁻¹.
 8. The process of claim 1 wherein the alkylation catalyst otherthan the fluorine-containing mordenite is hydrogen fluoride.
 9. Theprocess of claim 1 wherein the alkylation catalyst other than thefluorine-containing mordenite is aluminum chloride.
 10. A process usefulfor the production of linear alkylbenzene, comprising:combining aproduct from a linear alkylbenzene alkylation reactor that employs acatalyst other than a fluorine-containing mordenite catalyst with aproduct from a linear alkylbenzene alkylation reactor containingfluorine-containing mordenite, wherein the mordenite has been treated bycontacting the mordenite with an aqueous hydrogen fluoride solution,wherein the hydrogen fluoride in the aqueous solution has aconcentration in the range from about 0.1 percent to about 1 percent byweight.
 11. The process of claim 10 wherein the product from the linearalkylbenzene alkylation reactor that employs a catalyst other than afluorine-containing mordenite catalyst has a 2-phenyl isomer contentbelow about 30 percent by weight and wherein the product of themordenite reactor has a 2-phenyl isomer content above about 70 percentby weight.
 12. The process of claim 10 wherein the linear alkylbenzenealkylation reactor that employs a catalyst other than afluorine-containing mordenite catalyst is a hydrogen fluoride reactor.13. The process of claim 10 wherein the linear alkylbenzene alkylationreactor is an aluminum chloride reactor.
 14. A process for theproduction of linear alkylbenzene, comprising:dehydrogenating a paraffinto form an olefin; sending a primary feed stream of benzene and theolefin through a conduit to an alkylation reactor; contacting theprimary feed stream in the alkylation reactor with an alkylationcatalyst other than a fluorine-containing mordenite catalyst underconditions effective to react the benzene and olefin to form a firstlinear alkylbenzene product; withdrawing a portion of the primary feedstream from the conduit and contacting the portion with afluorine-containing mordenite under conditions effective to react thebenzene and olefin to form a second linear alkylbenzene product;combining the first and second linear alkylbenzene products to form acrude linear alkylbenzene stream; distilling the crude linearalkylbenzene stream in a first distillation column to separate benzenethat did not react and to form a benzene-free linear alkylbenzenestream; optionally distilling the benzene-free linear alkylbenzenestream in a second distillation column to separate any olefin and toform an olefin free linear alkylbenzene stream; distilling the olefinfree alkylbenzene stream in a third distillation column to provide anoverhead of a purified linear alkylbenzene product and removing abottoms stream containing any heavies, wherein the mordenite has beentreated by contacting the mordenite with an aqueous hydrogen fluoridesolution, wherein the hydrogen fluoride in the aqueous solution has aconcentration in the range from about 0.1 percent to about 1 percent byweight.
 15. The process of claim 14 further comprising recycling thebenzene from distillation of the crude linear alkylbenzene stream to theconduit.
 16. The process of claim 14 further comprising dewatering theportion of the primary feed stream prior to contact with thefluorine-containing mordenite.
 17. The process of claim 14 wherein thealkylation catalyst other than a fluorine-containing mordenite catalystis a hydrogen fluoride.
 18. The process of claim 14 wherein thealkylation catalyst other than a fluorine-containing mordenite catalystis aluminum chloride.